creating 3rd person character in unity

I created a cube and I have made simple animations for that cude; idle, walk, and jump. and I have dragged all of the 3rd person scripts that unity comes with and I have applyeed the animations to it. but its not working, it comes up the the error message "The AnimationClip 'idle' used by the Animation component 'Player' must be marked as Legacy." and NullReferenceException ThirdPersonController.Update () (at Assets/Standard Assets/Character Controllers/Sources/Scripts/ThirdPersonController.js:350)